Basement Furnace System: Turned on the heat and confirmed proper operation. Replaced the 20x25x1 filter and cleaned the blower cabinet and gas burners, which were in good working order with no signs of impingement. Blew out the condensate line for the condensing furnace. Checked electrical components, cleaned the flame sensor, and measured a temperature rise of 52 degrees (73/125). System is functioning properly. The filter cabinet is an older Lennox model with UV light bulbs. Recommended updating it for easier filter changes, but the homeowner is not interested at this time. Also noted that the humidifier is non-operational and suggested replacing it if dry air becomes an issue.
